The answer is D. If doctor was on its own you wouldn't capitalize it, but because it is next to his name you would capitalize the title; doctor.
The correct answer is indignant.
Being indignant means being angry or furious when you feel that something is unjust or outrageous, In this instance, Mrs. Fletcher is furious and outraged (indignant) that Mrs. Pike, who does not even know her (Mrs. Fletcher), knows about her pregnancy. Her indignance is further exemplified when she says, "The nerve of some people!".
It means in a context of a two-party system. Like if opposing parties find a common ground in a dispute.
